diff --git a/mlir/lib/CAPI/IR/IR.cpp b/mlir/lib/CAPI/IR/IR.cpp
--- a/mlir/lib/CAPI/IR/IR.cpp
+++ b/mlir/lib/CAPI/IR/IR.cpp
@@ -176,6 +176,12 @@
   for (unsigned i = 0; i < state->nRegions; ++i)
     cppState.addRegion(std::unique_ptr<Region>(unwrap(state->regions[i])));
 
+  free(state->results);
+  free(state->operands);
+  free(state->regions);
+  free(state->successors);
+  free(state->attributes);
+
   return wrap(Operation::create(cppState));
 }